Nivar

Nivar

Investigation of monthly changes in physical parameters and double diffusion structures in the Persian Gulf and the Strait of Hormuz

Document Type : Original Article

Authors
Mostafa Solgi 1
Abbasali Aliakbari Bidokhti 2
Smaeyl Hassanzadeh 3
Mahdi Mohammad Mahdizadeh 4
1 Department of Space Physics, Institute of Geophysics, University of Tehran, Iran and Department of Non-biological Atmospheric and Ocean Sciences, Faculty of Marine Science and Technologies, University of Hormozgan, Bandar Abbas, Iran
2 Department of Space Physics, Institute of Geophysics, University of Tehran, 14155-6466, Iran
3 Faculty of Physics, University of Isfahan, Isfahan, 81746-73441, Iran
4 Department of Non-Biologic Atmospheric and Oceanographic Science, Faculty of Marine Science and Technologies, University of Hormozgan, Bandar Abbas, 79177, Iran
10.30467/nivar.2025.511375.1327
Abstract
Climatic conditions and thermohaline exchange between two water basins in regions such as the Strait of Hormuz can provide the necessary conditions for the formation of structures dependent on vertical variations in temperature and salinity. One of the structures resulting from a vertical density gradient is known as the double‐diffusion process, which, based on the roles of temperature and salinity components, may occur in the form of salt fingers or diffusive convection. Accordingly, in this study, we attempted to investigate the monthly changes in the physical parameters of temperature and salinity in the Persian Gulf and the Strait of Hormuz, as well as the double‐diffusion structures along the exchange flow pathway in the western Strait of Hormuz, by implementing the HYCOM numerical model with 41 isopycnal layers, 14 sigma layers, and a resolution of 1/50 (0.02) degrees. The results of this study indicate that conditions for both double‐diffusion structures are unfavorable in March, but in April, salt fingers are intensified at the surface. The increase in temperature and salinity caused by evaporation in late summer always creates conditions for the formation of warm and saline water masses and the descent of salt fingers. However, these salt structures are often of the weak type. With the increase in outflow and its role in the stratification of the water mass in the western part of the strait, the salt structures become deeper. With the rise in salinity during autumn, salt fingers are strengthened at the surface, and several strong salt structures form at the surface and in the northern and southern parts of the western section of the Strait of Hormuz. Gradually, with the decrease in temperature and salinity, conditions become favorable for diffusive convection. Specifically, in December, a significant drop in temperature occurs in the western part of the strait, around 56°E, which creates suitable conditions for the formation of widespread diffusive convection.
Keywords
Persian Gulf
Strait of Hormuz
HYCOM model
Turner angle
salt fingers
diffusive convection
Subjects
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  • Receive Date 11 March 2025
  • Revise Date 02 September 2025
  • Accept Date 16 September 2025
  • Publish Date 21 March 2026